1. Field of the Invention
The invention relates to a method to use a mixer and to a mixer itself.
2. State of the Art
Several single-stage mixers are known from the most closely associated state of the art technology.
In DE 10 2006 024 778 B3, a mixer is described for which a wall structure for the flow guidance surfaces is provided, which essentially fills the profile of the housing, and thus causes a relatively high dynamic pressure loss. The wall structure is made of several layers of undulating strip material which is aligned parallel to the direction of flow. The individual layers respectively extend transverse to the direction of flow and are stacked on top of each other in an alignment which is transverse to the direction of flow. Here, the strip material in the individual layers is stacked on top of itself in such a manner that between the strip material of adjacent layers, a plurality of cells is formed which can respectively each be flowed through in the direction of flow.
Alongside the round undulation, it is also provided that the undulations of the strip material be designed with a rectangular or trapezoid form, as a result of which profiles for the individual cells can be achieved which are rectangular or hexagonal or with a honeycomb shape. The strip material forms a support onto which flow guidance surfaces are formed in pairs as mixing fins. For this purpose, the support comprises in alternation an area with a mixing fin and an area which is connected to it which has no mixing fins, so that one mixing fin extends into each cell.
In DE 20 2006 017 848 U1, a device for mixing exhaust gases is described with which a fin unit consisting of fins which are arranged directly following each other causes the exhaust gas to be mixed. The fin units are arranged transverse to the direction of flow adjacent to each other, and in the direction of flow one behind the other. The fins are connected to each other directly without a support, and are arranged in mirror symmetry in relation to a centre plane.
DE 10 2005 059 971 A1 describes a device for mixing a fluid with a large gas quantity flow which flows into a gas channel, in particular for the addition of a reduction agent into an exhaust gas which contains nitrogen oxide.
For this purpose, a nozzle lance with a nozzle for the delivery of the fluid is used, the axis of which forms an angle with the direction of flow of the gas quantity flow. The nozzle is assigned a flat mixer element with an interspace, which forms an angle with the direction of flow of the gas quantity flow. On the mixer element, flow eddies are formed, and at least a part of the fluid enters these flow eddies. In order to prevent the formation of a coating, it is provided that when a liquid is used as a fluid, the nozzle lance is equipped with at least two atomiser nozzles which are inclined against the direction of flow of the gas quantity flow and towards each other in the opposite direction. The atomiser nozzles are assigned to a disc-type mixer element so that a separation of evaporated gaseous parts and non-evaporated droplet parts is possible.
DE 10 2006 043 225 A1 describes an exhaust gas plant for a combustion machine with an exhaust gas line which guides the exhaust gas and an injection device for injecting a liquid into the exhaust gas line. Downstream from the injection device, an evaporation unit is provided in the exhaust gas line which comprises at least one tubular plate body which extends in a longitudinal direction of the exhaust gas line, and results in an improved evaporation of the injected liquid. Furthermore, a spring-type clamp device is provided which affixes the evaporation device in the exhaust gas line, or which tensions it against said exhaust gas line.
As the most closely associated state of the art technology, an exhaust gas system is described in DE 10 2005 052 064 A1 with an injection device for a reduction agent, in which downstream from the injection device, a plate body is arranged which comprises at least one wall which extends in the longitudinal direction of the exhaust gas line, and which is exposed to the exhaust gas flow on both sides. The reduction agent is sprayed at least partially onto the wall, resulting in a conversion of the liquid reduction agent into a vaporous or gaseous state.